Question

HELP PLZZZZZZ...A DVD rental box has a membership plan in which a person pays a flat fee for $10 plus $2.00 for each DVD rented. Non Members pay $4.50 for each DVD rented. How many DVDs would a person have to rent to make a membership plan a better deal?

Answer 1

let x = number of DVD's rented and y = total cost

Answer 2

if you have a membership, then it will cost $2 per DVD, so if you rent x of them, then you pay 2x dollars

then you add on the $10 flat fee

so the total cost equation for members is y = 2x + 10

Answer 3

For nonmembers, the cost equation is y = 4.50x because it costs $4.50 per DVD for nonmembers

Answer 4

You have these two equations

y = 2x + 10
y = 4.50x

find their point of intersection and tell me what you get

Answer 5

i got the intersection as (4,18) so wht is the meaning of this solution?

Answer 6

but whts the answer thn?.....more than 4 times?

Answer 7

That is correct. If you rent more than 4 DVDs, then the membership is the better deal.

Answer 8

but like, how?
to be honest, some1 else told me this answer. and i need to explain/justify my answer. but i dont know how?

Answer 9

y = 2x + 10 ... start with the first equation

4.50x = 2x + 10 ... plug in y = 4.50x

now solve for x

Answer 10

solving for x gives:

4.50x = 2x + 10

4.50x-2x = 10

2.50x = 10

x = 10/2.50

x = 4

Answer 11

And then you plug that back into either equation that has x,y in it

y = 2x + 10

y = 2*4 + 10

y = 18

Answer 12

But really all you need is that x value to answer this question

Answer 13

yes, i know that. but how does this help in finding out on How many DVDs would a person have to rent to make a membership plan a better deal?

Answer 14

at the point of intersection, the two deals cost the same (for the same number of DVDs rented)

Answer 15

This point of intersection is (4,18), ie x = 4, y = 18

basically this means that if you rent 4 DVDs, then it will cost $18 whether you are a member or a nonmember

Answer 16

renting more than 4 DVDs will be cheaper as a member because you're adding on $2 if you are a member (compared to adding on $4.50 for nonmembers)

Answer 17

Ohh. ok, now I get it. Thank you very much!

Answer 18

you're welcome